Ideas for fireproof printer enclosure

I have been thinking for a while on making a fireproof enclosure that would not let fire spread outside of the printer and would keep fumes of the ABS inside while printing. I want to let printer work overnight and while I am not around.
Self-extinguishing engineering plastics are quite pricey in quantities needed to cover a whole printer and while metal would be easier to obtain, it will require special tools to work with.
I came up with an idea of using ceramics. Low priced ceramics are often used in house building materials. First material that came to mind was a cement. Easy to cast by making form of polystyrene foam. But would end up being really heavy and process is quite messy so would require an acces to garden or similar place to make it.
Then I thought of plasterboard. Easy to cut and assemble and is fireproof. What do you think?

I guess I would go with a seperate plasterboard area under the printer where I would put power supply and electrical board so they get a little cooling by not being in a chamber area. A chamber on top of it would contain a whole printer and would have a removable top cover. In a seperate plasterboard box on the side I would put a material spool as ABS is a flammable material and it is a good idea to seperate it from the rest.
By seperating these parts of the printer I limit the fire spread and possible damage to the printer if fire would actually accour.

Any comments from fellow RepRapers are welcome.

Edited 1 time(s). Last edit at 05/03/2014 09:31AM by Edvardas.

Wouldn't you need to test this enclosure in some way ? Would you have a printer to spare ?

I haven't seen an example of cement board being used as a fire proof enclosure.
Construct a test to validate it's use for your application.

Consider adding standoffs to prevent the bottom from transferring heat.

Cement board
[en.wikipedia.org]


cement-bonded particle boards have higher capacity than cement fibre boards.

Cement fibre boards are more used in decorative applications

Typical cement fiber board is made of approximately 40-60% of cement, 20-30% of fillers, 8-10% of cellulose, 10-15% of mica.

joints are then filled with silicone sealant

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eci22
Wouldn't you need to test this enclosure in some way ? Would you have a printer to spare ?

It should be quite easy to make a small box of plasterboard and introduce a fire in it. When see what happens.
Enclosing a printer in some sort of box has been tested before so that should not be a problem.
In a case of fire I would have a printer to spare but would not have a flat to spare. So letting a printer to burn seems like better solution

i would have to say go with the cement board, thought it is not light, and i am not sure of the best way to frame it, that would buy you the most time, 2 layers of 1/2 drywall will buy you 30min of fire rating, i think. if i remember right, you could even look into some intumescent paints too wiki intumescent, so what kinda level of paranoid are you after any how.?

Edited 2 time(s). Last edit at 05/03/2014 05:04PM by dissidence.

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[mike-mack.blogspot.com]

Why not aluminum? Light weight,fairly cheap and easy to work with.

Alumininum melts at 1100f. It seldom survives a fire.

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dissidence
so what kinda level of paranoid are you after any how.?

Thank you for a message.

Not as paranoid as you can think. Initially I wanted to build an enclosure as I am tired of ABS fumes. But making that enclosure fireproof would bring a new opportunities of stand alone printing.

So far I have printed around 5 kilograms of ABS which translates to a few hundreds of hours without a problem but I really want to be on a safe side.

BTW, I saw this smoke detector: [www.ebay.co.uk] Programing it to shut down a powder supply seems like a great idea.

a good option might be a aluminum box then.

though if you are worried about fire look into some of those paints i mentioned. and paint that on the inside

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[mike-mack.blogspot.com]

What about plain old glass? It has a high melting point, high visibility, relitivally light, and since you are wanting it to contain the smell you will want to make it as air tight as possible. If a fire did break out inside it the oxygen would soon be all consumed and extinguish itself.

On the con side it is glass so it's fairly fragile, No more indoor baseball games.

Thanks
Mike

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garyhlucas
Alumininum melts at 1100f. It seldom survives a fire.

How is a fire going to reach 1100 degrees inside of a sealed chamber? By the time it even approached that temperature any plastic would have already smoldered or ignighted, consuming the oxygen and effectively snuffing out the flames. In the event of a thermal runaway of a build plate or hot end, a short likely would trip also long before melting point of the alumnium.

I wouldn't use alumnium not because of any danger in doing so, but because it's more expensive then just sheet steel.

Did you build it?

This guy's idea is cool.

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Miertam
What about plain old glass? It has a high melting point, high visibility, relitivally light, and since you are wanting it to contain the smell you will want to make it as air tight as possible. If a fire did break out inside it the oxygen would soon be all consumed and extinguish itself.

On the con side it is glass so it's fairly fragile, No more indoor baseball games.

Thanks
Mike

I don't think ordinary plasterboard is a suitable material. It is just made from gypsum on a canvas backing. It does not have the fire resistance. Fire cement could be used to cast an enclosure. It is fairly easy to work with and you could make a big box. If you look on YouTube there are lots of examples of home made furnaces. It may be suitable to house such an enclosure in the garage or basement on a solid concrete floor. It would not be very practical though. It would be heavy. Wall thickness would be maybe 1 to 2 inches thick. Access to the printer would be a problem unless your printer is small enough to lift in and out.

I think a metal enclosure is easier to fabricate and more practical to use. Sheet steel, say 1/8" thick, would be my material of choice. Thin aluminium can burn through even if it does not reach its melting point. I would not personally print in the main house overnight. It is a big risk. Away from the house in an enclosure is safer.

I also don't think any home made enclosure can be made gas tight. Any slight pressure and fumes are going to leak out. I think the enclosure needs a fume duct to the outside with some sort of extractor fan. Couple this with a smoke alarm that cuts the power and ideally gives a timed blast from a nitrogen or CO2 cylinder.

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dave3d
I don't think ordinary plasterboard is a suitable material. It is just made from gypsum on a canvas backing.

It's not, but there IS fire-rated gypsum board. Here's an example:

[www.homedepot.com]

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"I have noticed that even those who assert that everything is predestined and that
we can change nothing about it still look both ways before they cross the street"

-Stephen Hawking

If you use the fire resistant board and the fire detector for arduino could you have it set off a alarm and bump a bucket of sand on the printer

If you put the sand into a styrofoam bucket and leave it on top of the printer/enclosure, it will dump itself onto the fire in he presence of flames hot enough to melt the styrofoam. We used to have styrofoam suspended ceiling tiles at work with the fire sprinklers above them, and it was allowed by fire code because the tiles would melt and drop out in the event of a fire before it got hot enough to trigger the sprinklers. I don't know how they overlooked the noxious fumes from burning styrofoam, and am wondering in retrospect if it wasn't a special foam?????

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vreihen
If you put the sand into a styrofoam bucket and leave it on top of the printer/enclosure, it will dump itself onto the fire in he presence of flames hot enough to melt the styrofoam. We used to have styrofoam suspended ceiling tiles at work with the fire sprinklers above them, and it was allowed by fire code because the tiles would melt and drop out in the event of a fire before it got hot enough to trigger the sprinklers. I don't know how they overlooked the noxious fumes from burning styrofoam, and am wondering in retrospect if it wasn't a special foam?????

Doesn't really matter at that point. A fire big enough to melt the tiles (or set off the sprinkler head) would have killed you by smoke inhalation already. You should be beatin' feet LONG before then!

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"I have noticed that even those who assert that everything is predestined and that
we can change nothing about it still look both ways before they cross the street"

-Stephen Hawking

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andy.wpg

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vreihen
If you put the sand into a styrofoam bucket and leave it on top of the printer/enclosure, it will dump itself onto the fire in he presence of flames hot enough to melt the styrofoam. We used to have styrofoam suspended ceiling tiles at work with the fire sprinklers above them, and it was allowed by fire code because the tiles would melt and drop out in the event of a fire before it got hot enough to trigger the sprinklers. I don't know how they overlooked the noxious fumes from burning styrofoam, and am wondering in retrospect if it wasn't a special foam?????

Doesn't really matter at that point. A fire big enough to melt the tiles (or set off the sprinkler head) would have killed you by smoke inhalation already. You should be beatin' feet LONG before then!

if its inside the closer then a smoke detector can alert you the fire hazard and the sand can be putting the fire out containing it inside the closer

and if your printer in in shed work shop at least you come back to a dead reprap and not a pile of ash where your shed work shop use to be even worse in the house

I had an idea a while ago, I made a design for it but my computer has since been stolen.

The idea is that you have an enclosure, any material, as long as it's relatively sealed. You use your chamber's temp sensor in conjunction with the hotend/bed sensors to detect a fire. (wouldn't be difficult, a rapid rise or anything over like 100C in the chamber)

Then, in a little case tucked under the print bed or wherever are two or 3 of those little CO2 canisters they use in toy airguns and whatnot. A little servo or motor or solenoid pops the top and the chamber instantly fills with CO2, putting out the fire. I've popped a few by hand before and there is definitely enough gas for a small fire, but not enough to be dangerous.

Benefits: Super cheap, (<$10) reusable, and best of all, won't ruin your printer more than the fire.

it's not a perfect, 100% fireproof system, but I bet if done right it could add a significant amount of safety.